Background: Acquired hemophilia A (AHA) is an autoimmune disease characterized by the development of autoantibodies against coagulation factor VIII (FVIII). AHA most commonly occurs spontaneously in older adults, but can be triggered by malignancy, autoimmune disease, pregnancy, infection, and drugs, particularly antibiotics. We report a rare case of AHA diagnosed in the setting of GI bleeding refractory to numerous endoscopic treatments.

Case Presentation: A 71-year-old man with coronary artery disease who was initially hospitalized for cellulitis that did not respond to multiple prolonged courses of outpatient antibiotics developed a GI bleed. On admission, he was placed on cefazolin and developed hematemesis 4 days later. Endoscopy identified an oozing gastroesophageal junction (GEJ) ulceration with a visible blood vessel. It was treated with epinephrine injections, hemostatic clips, and spray. The patient was readmitted twice shortly after discharge for recurrent bleeding, first for melena and then for hemorrhagic shock. He received four total endoscopies finding active bleeding at the GEJ, all with successful procedural hemostasis. Coagulopathy workup revealed a persistently elevated prothrombin time, with only partial correction in mixing studies. Further testing identified the specific FVIII inhibitor, quantified its high titer of 71 Besthesda Units, and confirmed extremely low FVIII activity (<1%) diagnostic for an acquired FVIII deficiency. Sulfasalazine was considered the most likely inducer. The bleeding stopped after fresh frozen plasma transfusions, and he was discharged home on corticosteroids, with plans to start rituximab.

Discussion: This case underscores the consideration of coagulopathies as possible contributors to refractory anemia and GI bleeding. Recent antibiotics should increase suspicion of AHA, even without a prior history of abnormal coagulation. This approach can lead to timely and appropriate treatment interventions, such as immunosuppressive therapy and FVIII replacement, ultimately improving patient outcomes. Despite its rarity, awareness and suspicion of AHA can significantly impact the management and prognosis of affected patients.